glRasterPos(3G)		       OpenGL Reference		       glRasterPos(3G)



NAME
     glRasterPos2d, glRasterPos2f, glRasterPos2i, glRasterPos2s,
     glRasterPos3d, glRasterPos3f, glRasterPos3i, glRasterPos3s,
     glRasterPos4d, glRasterPos4f, glRasterPos4i, glRasterPos4s,
     glRasterPos2dv, glRasterPos2fv, glRasterPos2iv, glRasterPos2sv,
     glRasterPos3dv, glRasterPos3fv, glRasterPos3iv, glRasterPos3sv,
     glRasterPos4dv, glRasterPos4fv, glRasterPos4iv, glRasterPos4sv - specify
     the raster	position for pixel operations


C SPECIFICATION
     void glRasterPos2d( GLdouble x,
			 GLdouble y )
     void glRasterPos2f( GLfloat x,
			 GLfloat y )
     void glRasterPos2i( GLint x,
			 GLint y )
     void glRasterPos2s( GLshort x,
			 GLshort y )
     void glRasterPos3d( GLdouble x,
			 GLdouble y,
			 GLdouble z )
     void glRasterPos3f( GLfloat x,
			 GLfloat y,
			 GLfloat z )
     void glRasterPos3i( GLint x,
			 GLint y,
			 GLint z )
     void glRasterPos3s( GLshort x,
			 GLshort y,
			 GLshort z )
     void glRasterPos4d( GLdouble x,
			 GLdouble y,
			 GLdouble z,
			 GLdouble w )
     void glRasterPos4f( GLfloat x,
			 GLfloat y,
			 GLfloat z,
			 GLfloat w )
     void glRasterPos4i( GLint x,
			 GLint y,
			 GLint z,
			 GLint w )
     void glRasterPos4s( GLshort x,
			 GLshort y,
			 GLshort z,
			 GLshort w )








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glRasterPos(3G)		       OpenGL Reference		       glRasterPos(3G)



PARAMETERS
     x,	y, z, w
	      Specify the x, y,	z, and w object	coordinates (if	present) for
	      the raster position.

C SPECIFICATION
     void glRasterPos2dv( const	GLdouble *v )
     void glRasterPos2fv( const	GLfloat	*v )
     void glRasterPos2iv( const	GLint *v )
     void glRasterPos2sv( const	GLshort	*v )
     void glRasterPos3dv( const	GLdouble *v )
     void glRasterPos3fv( const	GLfloat	*v )
     void glRasterPos3iv( const	GLint *v )
     void glRasterPos3sv( const	GLshort	*v )
     void glRasterPos4dv( const	GLdouble *v )
     void glRasterPos4fv( const	GLfloat	*v )
     void glRasterPos4iv( const	GLint *v )
     void glRasterPos4sv( const	GLshort	*v )


     v	  Specifies a pointer to an array of two, three, or four elements,
	  specifying x,	y, z, and w coordinates, respectively.


DESCRIPTION
     The GL maintains a	3-D position in	window coordinates.  This position,
     called the	raster position, is maintained with subpixel accuracy.	It is
     used to position pixel and	bitmap write operations.  See glBitmap,
     glDrawPixels, and glCopyPixels.

     The current raster	position consists of three window coordinates (x, y,
     z), a clip	coordinate w value, an eye coordinate distance,	a valid	bit,
     and associated color data and texture coordinates.	 The w coordinate is a
     clip coordinate, because w	is not projected to window coordinates.
     glRasterPos4 specifies object coordinates x, y, z,	and w explicitly.
     glRasterPos3 specifies object coordinate x, y, and	z explicitly, while w
     is	implicitly set to one.	glRasterPos2 uses the argument values for x
     and y while implicitly setting z and w to zero and	one.

     The object	coordinates presented by glRasterPos are treated just like
     those of a	glVertex command:  They	are transformed	by the current
     modelview and projection matrices and passed to the clipping stage.  If
     the vertex	is not culled, then it is projected and	scaled to window
     coordinates, which	become the new current raster position,	and the
     GL_CURRENT_RASTER_POSITION_VALID flag is set.  If the vertex is culled,
     then the valid bit	is cleared and the current raster position and
     associated	color and texture coordinates are undefined.

     The current raster	position also includes some associated color data and
     texture coordinates.  If lighting is enabled, then
     GL_CURRENT_RASTER_COLOR, in RGBA mode, or the GL_CURRENT_RASTER_INDEX, in
     color index mode, is set to the color produced by the lighting



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glRasterPos(3G)		       OpenGL Reference		       glRasterPos(3G)



     calculation (see glLight, glLightModel, and glShadeModel).	 If lighting
     is	disabled, current color	(in RGBA mode, state variable
     GL_CURRENT_COLOR) or color	index (in color	index mode, state variable
     GL_CURRENT_INDEX) is used to update the current raster color.

     Likewise, GL_CURRENT_RASTER_TEXTURE_COORDS	is updated as a	function of
     GL_CURRENT_TEXTURE_COORDS,	based on the texture matrix and	the texture
     generation	functions (see glTexGen).  Finally, the	distance from the
     origin of the eye coordinate system to the	vertex as transformed by only
     the modelview matrix replaces GL_CURRENT_RASTER_DISTANCE.

     Initially,	the current raster position is (0,0,0,1), the current raster
     distance is 0, the	valid bit is set, the associated RGBA color is
     (1,1,1,1),	the associated color index is 1, and the associated texture
     coordinates are (0, 0, 0, 1).  In RGBA mode, GL_CURRENT_RASTER_INDEX is
     always 1; in color	index mode, the	current	raster RGBA color always
     maintains its initial value.

NOTES
     The raster	position is modified both by glRasterPos and by	glBitmap.

     When the raster position coordinates are invalid, drawing commands	that
     are based on the raster position are ignored (that	is, they do not	result
     in	changes	to GL state).

ERRORS
     GL_INVALID_OPERATION is generated if glRasterPos is executed between the
     execution of glBegin and the corresponding	execution of glEnd.

ASSOCIATED GETS
     glGet with	argument GL_CURRENT_RASTER_POSITION
     glGet with	argument GL_CURRENT_RASTER_POSITION_VALID
     glGet with	argument GL_CURRENT_RASTER_DISTANCE
     glGet with	argument GL_CURRENT_RASTER_COLOR
     glGet with	argument GL_CURRENT_RASTER_INDEX
     glGet with	argument GL_CURRENT_RASTER_TEXTURE_COORDS


SEE ALSO
     glBitmap, glCopyPixels, glDrawPixels, glLight, glLightModel,
     glShadeModel, glTexCoord, glTexGen, glVertex














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